To enable ABIs which store extra info in the frame, add two new slots to
the coroutine allocator function table. For example, a frame could have
a header containing a context pointer at a negative offset from the
address returned from `swift_coro_alloc_frame`. The frame deallocation
function would then know to deallocate more space correspondingly.
Allocator structs are passed in to new ABI yield-once coroutines and
contain pointers to functions to de/allocate memory. Here, those
pointers are signed.
Ensure that context descriptor pointers are signed in the runtime by putting the ptrauth_struct attribute on the types.
We use the new __builtin_ptrauth_struct_key/disc to conditionally apply ptrauth_struct to TrailingObjects based on the signing of the base type, so that pointers to TrailingObjects get signed when used with a context descriptor pointer.
We add new runtime entrypoints that take signed pointers where appropriate, and have the compiler emit calls to the new entrypoints when targeting a sufficiently new OS.
rdar://111480914
rdar://105837040
* WIP: Store layout string in type metadata
* WIP: More cases working
* WIP: Layout strings almost working
* Add layout string pointer to struct metadata
* Fetch bytecode layout strings from metadata in runtime
* More efficient bytecode layout
* Add support for interpreted generics in layout strings
* Layout string instantiation, take and more
* Remove duplicate information from layout strings
* Include size of previous object in next objects offset to reduce number of increments at runtime
* Add support for existentials
* Build type layout strings with StructBuilder to support target sizes and metadata pointers
* Add support for resilient types
* Properly cache layout strings in compiler
* Generic resilient types working
* Non-generic resilient types working
* Instantiate resilient type in layout when possible
* Fix a few issues around alignment and signing
* Disable generics, fix static alignment
* Fix MultiPayloadEnum size when no extra tag is necessary
* Fixes after rebase
* Cleanup
* Fix most tests
* Fix objcImplementattion and non-Darwin builds
* Fix BytecodeLayouts on non-Darwin
* Fix Linux build
* Fix sizes in linux tests
* Sign layout string pointers
* Use nullptr instead of debug value
Two protocol conformance descriptors are passed to
swift_compareProtocolConformanceDecriptors from generic metadata
accessors when there is a canonical prespecialization and one of the
generic arguments has a protocol requirement.
Previously, the descriptors were incorrectly being passed without
ptrauth processing: one from the witness table in the arguments that are
passed in to the accessor and one known statically.
Here, the descriptor in the witness table is authed using the
ProtocolConformanceDescriptor schema. Then, both descriptors are signed
using the ProtocolConformanceDescriptorsAsArguments schema. Finally, in
the runtime function, the descriptors are authed.
